@duckycline besides the great answer by @mayer, the very first thing you want to do is to not try to restart the phone. This may further damage your phone. The next thing to do is to clean it. Disassemble your phone using these guides Remove all EMI shields from your phone, then clean it with +90% isopropyl alcohol. Follow this guide, and even so it was written for an Apple iPhone 3G all the points are still pertinent to your phone. While you clean your board, check for any obvious damage, like burned or missing components etc. When it is properly cleaned, replace the battery. All these steps are to avoid delayed failure caused by corrosion. Best way to clean it would of course be through an ultrasonic cleaner, so you may consider a professional service . Once all this is done, reassemble your phone and reevaluate.

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